strpos case insensitive php

1stripos ( string $haystack , string $needle , int $offset = 0 ) : int|false
2  
3<?php
4  $findme    = 'a';
5  $mystring1 = 'xyz';
6  $mystring2 = 'ABC';
7
8  $pos1 = stripos($mystring1, $findme);
9  $pos2 = stripos($mystring2, $findme);
10
11  // Nope, 'a' is certainly not in 'xyz'
12  if ($pos1 === false) {
13    echo "The string '$findme' was not found in the string '$mystring1'";
14  }
15
16  // Note our use of ===.  Simply == would not work as expected
17  // because the position of 'a' is the 0th (first) character.
18  if ($pos2 !== false) {
19    echo "We found '$findme' in '$mystring2' at position $pos2";
20  }
21?>